Monoazo pigments



United States Patent O1 ifice 3,509,123 Patented Apr. 28, 1970 U.S. Cl.266-193 6 Claims ABSTRACT 6F THE DISCLOSURE Monoazo dyestuffs of theformula Xi COCH3 Y1 Z in which A is a naphthyl radical or a benzeneradical which may be substituted by halogen atoms, lower alkyl or loweralkoxy groups, X, represents a halogen atom, a lower alkyl, lower alkoxyor carbo-lower alkoxy group, Y is a hydrogen or halogen atom, Z and Zeach represents a hydrogen or halogen atom, lower alkyl, trifluoromethylor lower alkoxy group and R is a hydrogen atom, a lower alkyl, a phenyllower alkyl or a phenyl radical which may be substituted by halogenatoms, lower alkyl, trifiuoromethyl or lower alkoxy groups, are valuablepigments which yield yellow dyings of excellent fastness properties,when incorporated in pastics and lacquers.

The present invention is based on the observation that valuable newmonoazo dyestuff pigments of the formula in which A represents anunsubstituted or substituted benzene (containing up to threesubstituents), naphthalene or benzthiazole residue, B and B eachrepresents an unsubstituted or substituted benzene radical, and X acarboxylic acid arylide, aroylamino, ureido, alkylureido or arylureidogroup, can be obtained by condensing an azo dyestuif carboxylic acidhalide of the formula COCH;

A-NH O OOHN=NBiCOHal with a monoamine the formula (3) H NB X Since thedyestuffs of this invention are pigments, they must not contain groupsimparting solubility in water, particularly sulphonic acid andcarboxylic acid groups.

Especially valuable pigments can be obtained by condensing a carboxylicacid chloride of the formula COG] in which A has the above meaning, Xrepresents a halogen atom or an alkyl, alkoxy or carbalkoxy group and Y;a hydrogen or halogen atom, with a monoamine of the formula in which Rrepresents a hydrogen atom, an alkyl or aralkyl group or a benzeneradical which may be substituted with up to two substituents, forexample, by a halogen atom or an alkyl, trifluoromethyl, alkoxy, cyano,nitro, carbalkoxy, alkanoylamino or carbamide group, and Z and Z eachrepresents a hydrogen or halogen atom or an alkyl, trifiuoromethyl oralkoxy group.

The carboxylic acids from which the acid halides are derived may beobtained by coupling a diazo compound of an aminobenzoic acid,especially one of the formula I O A-NHC O OH:

in which X Y and A have the above meanings. As examples of aminobenzoicacids of the Formula 6 the following may be mentioned:3-amino-4-chlorobenzoic acid, 3-amino-4-methylbenzoic acid,3-amino-4-methoxybenzoic acid, 3-amino-4,6-dichlorobenzoic acid,3-amino- 4-methoxy-6-chlorobenzoic acid, 3 amino 4 carbomethoxybenzoicacid, 3-amino-4-carbethoxybenzoic acid and 4-amino-3-methylbenzoic acid.

The compounds of Formula 7 may be obtained simply by reacting a diketeneor acetoacetic ester with an aromatic monoamine, for example:2,5-dimethoxy-4-chloroaniline, 2,5-din1ethoxy-4-bromoaniline,2,5-diethoxy-4- chloroaniline, 2,S-diethoxy-4-bromoaniline,2,4-dimethylaniline, 2-chloroaniline, 2-methoxyaniline, 2-methoxy-4-benzoylamino-5-chloroaniline, a-naphthylamine or6-ethoxy-2-aminobenzthiazole.

The azo dyestulf monocarboxylic acids can be treated with agents capableof converting carboxylic acids into their acid halides, for example thebromides or chlorides, for example with phosphorus trichloride,pentachloride or oxychloride, or preferably with thionyl chloride. Thetreatment with such acid-halogenating agents is advantageously carriedout in an inert organic solvent, for example a chlorobenzene, forexample monoor dichlorobenzene, toluene, xylene, benzene ornitrobenzene. When thionyl chloride is used as acid-chlorinating agent,it is advantageous to work in the presence of a dialkylformamide,especially dimethylformamide.

In the manufacture of the carboxylic acid halides it is generallyadvantageous first to dry the azo compounds prepared in an aqueousmedium or to free them from water by azeotropic distillation in anorganic solvent. If desired, the azeotropic drying may be carried outimmediately before the treatment with the acid-halogenating agent.

The carboxylic acid halides obtained in this manner may be reacted withmonoamines, especially those of the Formula 5.

As examples of monoamines the following may be mentioned:

(a) AMINES CONTAINING A UREA GRO'UP 4-aminodiphenylurea,4-amino-4-methyldiphenylurea, 4-amino-4'-methoxydiphenylurea,4-amino-4'-chlorodiphenylurea, 4-amino-2,S-dimethyldiphenylurea,4-amino-2,5-dimethyl-4'-chlorodiphenylurea,4-amino-2,S-dichlorodiphenylurea, 4-amino-2,5,4'-trichlorodiphenylurea,4-amino-2-methyl-S-chlorodiphenylurea,4-amino-2-methoxy-5-chlorodiphenylurea,4-amino-2-methoxy-5,4-dichlorodiphenylurea,4-amino-2,5-dichloro-4-methoxydiphenylurea,4-amino-2,4'-dichlorodiphenylurea, 4-amino-2-chlo ro-3-trifiuoromethyldiphenylurea, 4-amino-2,S-dimethylphenyl-m-naphthylurea,4-aminophenyl-a-naphthylurea,4-amino-2,5-dimethyl-4'-methoxydiphenylurea, 4-amino-5-methoxy-Z-chlorodiphenylurea, 4-amino-2-chloro-5'-trifiuoromethyldiphenylurea, 4-amino-2'-chloro-5 -carb ornethoxydiphenylurea, 4-amino-2,4'dichlorodiphenylurea,4-amino-4-methoxydiphenylurea, 4-amino-4'-acetylaminodiphenylurea,4-amino-4-carbomethoxydiphenylurea,4-amino-2,5-dimethylphenylbenzylurea,4-amino-2,5-dimethyl-4-acetylaminodiphenylurea, 4-aminophenylmethylurea,4-amino-2,5-dimethylphenylmethylurea, 4-amino-2,5-dichlorophenylmethylurea, 4-amino-2,S-dichlorophenylurea,4amino-2,5-dimethylphenylurea and 4-aminophenylurea.

(b) BENZOYLAMINOANILINES 2 5 -dichloro-4-benzoylaminoaniline,

2,5-dichloro-4- (4'-chlorobenzoylamino) -aniline,

2,5 -dichloro-4- 2,4-dichlorobenzoylamino) -aniline,

2, 5 -dichloro-4- (4-rnethylbenzoylamino -aniline,

2,5-dichloro-4- (4-phenylbenzoylamino) -aniline,

2,5 -dimethyl-4-benzoylamino-aniline,

2,5-dimethyl-4- 4-chlorobenzoylamino -aniline,

2,5 -dimethyl-4- (4'-methylbenzoylamino) -aniline,

2,5 -dimethyl-4- (4'-phenylbenzoylamino) -aniline,

2, 5-dimethyl-4- (4'-methoxybenzoylamino) -aniline,

2-methoxy-5 -chloro-4-benzoylamino-aniline,

2-methoxy-5 -chlo ro-4- (4-chlorobenzoylamino aniline,

2-chloro-5-methoxy-4- (4-chlorobenzoylamino aniline and2-chloro-5-methoXy-4-(4'-phenylbenzoylamino) -aniline.

(c) AMINOBENZOIC ACID ARYLAMIDES 4-aminobenzoic acid phenylarnide,

4-aminobenzoic acid-4-chlorophenylamide,

4-aminobenzoic acid-2',4-dichlorophenylamide,

4-aminobenzoic acid-2-chloro-5'-trifluoromethylphenylamide,

4-amino-3-methylbenzoic acid-3-trifluorornethylphenylamide,

4-amino-3-methylbenzoic acid-4'-chlorophenylamide,

4-chloro-3-aminobenzoic acid phenylamide,

4-chloro-3-aminobenzoic acid-2',4'-dichlorophenylamide,

4-chloro-3-aminobenzoic acid-2,5'-dichlorophenylamide,

4-methyl-3-aminobenzoic acid phenylamide and 4-methoxy-3-aminobenzoicacid-4-chlorophenylamide.

The condensation of the carboxylic acid halides of the kind definedabove with the amine is advantageously carried out in an anhydrousmedium; when this is done, it generally proceeds surprisingly easilyeven at tempera tures within the boiling range of the common organicsolvents for example toluene, monochlorobenzene, dichlorobenzene,trichlorobenzene, nitrobenzene or the like. To accelerate the reactionit is in general advisable to add an acid acceptor, for exampleanhydrous sodium acetate or pyridine.

Some of the resulting dyestufis are crystalline and others are amorphousand in most cases they are ob tained in very good yields and in a purestate. It is advantageous first to isolate the acid chlorides obtainedfrom the carboxylic acids, though in some cases this can be omittedwithout harmful elfects, and the condensation carried out immediatelyafter the manufacture of the carboxylic acid chlorides.

The new dyestulfs are valuable yellow pigments suitable for a Widevariety of pigment applications, for example in a finely disperse formfor dyeing rayon and viscose or cellulose ethers and esters orpolyamides, polyurethanes or polyesters in the spinning mass. They mayalso be used for the manufacture of coloured lacquers or lakes,solutions and products from acetylcellulose, nitrocellulose, naturalresins or synthetic resins, for example polymerization resins orcondensation resins, for example aminoplasts, alkyd resins, phenoplasts,polyolefines for example polystyrene, polyvinylchloride, polyethylene,polypropylene, polyacrylonitrile, rubber, casein, silicone and siliconeresins. Moreover, they can be used with advantage in the manufacture ofcoloured pencils, cosmetics or laminated panels.

In contrast with the nearest comparable dyestuffs of Germanspecification No. 1,213,553 the pigments of this invention aredistinguished by their better fastness to light.

Unless otherwise indicated, parts and percentages in the followingexamples are by weight.

Example 1 7.7 parts of the dyestutf obtained from 1 mol of diazotized 3amino 4 chlorobenzoic acid and 1 mol of 2,5 dimethoxy 4 chloro 1acetoacetylamino-benzene of the formula CH; 0 CH3 1 c1 c1 NEG 0 (HI IN=N o C H;

COOH

are stirred in 460 parts of ortho-dichlorobenzene together with 0.5 partof dimethylformamide and heated to C. At this temperature 2.85 parts ofthionyl chloride are added Within 5 minutes and the Whole is stirred for2 hours at 130 C. The end of the reaction is recognized by the cessationof the evolution of hydrochloric acid and a specimen of the batchshowing uniform yellow needles under a microscope. The batch is allowedto cool to 30 C. and suction filtered. The filter residue is Washed with200 parts of benzene, then with 150 parts of petroleum ether and driedunder vacuum at 50 to 60 C. to yield 7.1 parts of the dyestutt acidchloride as a yellow, crystalline powder.

4.75 parts of the acid chloride thus Obtained are stirred in 100 partsof ortho-dichlorobenzene with 0.2 part of thionyl chloride and heated to80 to 85 C. A warm solution of 3.0 parts of4-amino-2',4'-dichlorodiphenylurea in 460 parts of orthodichlorobenzeneis then added and the whole is heated for 12 hours at -145 C. Thepigment formed is then suction filtered While hot and washed with hotortho-dichlorobenzene until the filtrate runs colourless. Thedichlorobenzene is then displaced with cold methanol and the product isthoroughly washed X1 with hot water and dried at 60-90 C. to yield 6.1parts 000m Y1 of a soft powder which is substantially insoluble in theANHOOJJHN=N Z1 common solvents. When rolled into polyvinylchloride, itproduces vivid yellow shades having good fastness to migration andlight. The pigment corresponds to the formula Z2 CONH NHCONHR1 CH; OCH

I I o (3 H3 0 o NHONHC 041110-01 The following table lists furthercomponents from which monoazo pigments can be obtained by the processwherein A is selected from the group consisting of naphdescrlbed above ycoupllng 1 11101 of a diaZO Compound thyl, phenyl and substituted phenylcontaining up to three of the aminocarboxyuc acid in m Wit]? 1 mol ofsubstituents, wherein the substituents are selected from the acetoacetylcompound of the amine listed in Column II, converting the resultingmonoazo dyestufl? carboxylic the group conslsmig of chloro bromo Iowaalkyi acid into its acid chloride and condensing the latter with loweralkoxy; 1 18 Selected rom the group consisting 1 mol of the amine shownin Column IH. Column 1V 0f chloro, lower y lower alkOXy and Garb-lowershows the shade produced with the resulting pigment in a1koxy;Y isselected from the group consisting of hydroa polyvinylchloride foil.

I II III IV 2,S-dimethoxy-4-chloroaniline4-am1'no-2'rnethoxy-5A-dichlorodiphenylurea Reddish yellow.

do 4 amino-2,4-diehlorodiphenylurea D0. .d04-aminc-2,5-dichlorodiphenylurea Yellow. .do. 4-arninodiphe nylurea Do..dO. 4-a1n1no-2,5-d1methyldiphenylurea Do. .do.4-amino-2,5-dimethyl-4-chlorodiphenylurea D0. .d0.4-amino-2-methoxy-5-chloridiphenylurea Greelnish ye ow.*l-aminophenylmethylurea. D0. 4-amino-4-rnethoxydiphenylurea Reddishyellow. 4 amlno-2,5-dimethylphenylbenzylurea Grefinish ye ow.4amino-2,4-dichlorodiphenylurea Yellow. 4-amino-25-diehlorlphenylmethylurea Do. 4-amino-2-chloro-5-trifiuoromethyldiphenylurea. Redltllish ye ow. 14 ..do do3-amino-4-methyl-2,5-dichlorodiphenylurea Yellow.2,5-dimethoxy-4bromoanihnec 4-amino-2,5-diehlorophenylurea Do. do4amino-2,5-dichlorodiphenylurea D0. 4-amino-2,fi-dlmethyldiphenylureaDo. 4-amino-2,4-dichlorodiphenylurea Greelnlsh ye ow. l9 do .do4-amino-4-chlorodiphenylurea t t Reddish yellow. .do .d04-arnilno-Z-mgthoxy-chloro-(4'-acetylamino)-b n- Yellow.

zoy amino enzene. 21 do do 4-amin0-2,5-diethoxydiphenylurea Do. 223-amin0-4,6-diehlorobenzoic aeid 2,5-dimethoxyA-chloroaniline4-amino-2,5-dimethyl-4-chlorodiphenylurea Do.

do do I 4-amino-2,5-dichlorodiphenylurea Reddish yellow.

do. 4-amino-2-methoxy-S-chloridiphenylurea Yellow. go.ai-aminoj,4-(%ic%1lorod%)hs;lnyhrea Do. 11 0 amin0 -ace yamino ip enyurea... Greenish ye ow. 27 3-a.mi1104-chl0robenz0ic aeid2rnetl10xylaniline 4-amino-4-chlorodiphenylurea Yellow. 28..-"3arnino-4,6-dichlorobenzoic acid-.- 2,5-dirnethoxyA-chloroaniline 4-amino-methoxy-5-chloro-(2,4-dichloro)-benzoyl- D0.

amino enzene. 29 do do 4-amino-2,5,3-trichlorodiphenylurea Reddishyellow. 30 3-amino-4-methylbenzoie acid- .d04-amino-2'-4-dichl0rodiphenylurea Greenish yellow. 31 do d04-amin0-2,S-dimethyldiphenylurea I Do. .do.4-am1'no-2,S-dichlorodiphenylurea Do. do4-amino-2,5-dimethy14-ehlorodiphenylurea Do. .do4-amino-2-methoxy-Schloro-l-benzoylaminobenzene Do. do4-amino-2-methoxy-5-chloridiphenylurea Very greenish y ow. do4-aminoQ-ethoxy-fi-chlorodiphenylurea D a-Naphthylamine4-amino-2-chloro-fi-methoxydiphenylurea 0. Reddish yellow Yellow.

do 4-amino 2,5-dimethyl-diphenylurea do 4-amino-4-chlorodiphenylurea Do.4-an1ino-2,5-diehlorodiphenylurea. Do.

Example 2 gen and chloro; Z and Z are each selected from the group partsof stabilized polyvinylchloride, 35 parts of Consisting of hydrogen,chloro, lower alkyl, tfifluofo' dioctyl lJhthalate and P 9 the y fiObtained methyl and lower alkoxy; and R is selected from the accordingto Example 1 are stlrred together and then group onsisting of hydrogen,lower alkyl, phenyl, phenyl rolled to and fro on a two-roll calender for7 minutes at 140 C The resulting greenish yellow foil has y lower alkyland substituted phenyl containing up to two good fasmess to light andmiuratiom substituents, wherein the substituents are selected from 1 l ia the group consisting of chloro, lower alkyl, trifluoromethyl 1. Amonoazo dyestufi pigment of the formula and lower alkoxy.

2. The dyestuif as claimed in claim 1 of the formula 3. The dyestufi asclaimed in claim 1 of the formula CH3 0 CH 0 (1; CH C1 NHC O l H (B N=NC1 3 [1 CONHQ-NHC 0NH- 4. The dyestuff as claimed in claim 1 of theformula 01 c1- NHCOOH O CH;

5. The dyestuff as claimed in claim 1 of the formula 6. The dyestuff asclaimed in claim 1 of the formula OCH E OCH OCH; i i

l OONHO-NHCONHB 40 GONHO-JN'HCONHCH;

References Cited FOREIGN PATENTS 1,213,553 3/1966 Germany.

CHARLES B. PARKER, Primary Examiner C. F. WARREN, Assistant Examiner US.Cl. X.R.

